Grow lights are artificial light sources configured to provide light to plants for horticulture. Grow lights are typically electrically powered and provide light to support a plant's growth through photosynthesis and other photochemical processes during plant growth. Typical horticultural facilities use grow lights as both sole light in indoor growing facilities and supplemental light for greenhouses.
Supplemented greenhouses are enclosed by a light transmissive (transparent or translucent) material such as glass, rigid plastic and plastic film. The transmissive material admits sunlight into the greenhouse, so that plants in the greenhouse receive sunlight to promote photosynthetic growth (growth through photosynthesis). Electric lights, mounted above the plants, augment the hours of light and intensity of light provided to the plants, to promote growth.
In indoor growing facilities, plants are grown indoors, in a building structure with opaque walls. The plants therefore lack significant exposure to sunlight for plant growth. Substantially all of the light for plant growth is provided by grow lights that are mounted high above the plants. Indoor growing facilities are typically of two types—non-stacked and stacked.
In non-stacked indoor growing facilities, plants are typically grown in trays in a single layer, typically on a floor. Grow lights are suspended from the ceiling of the indoor growth facility.
In stacked indoor growing facilities, also called vertical indoor growing facilities, plants are typically grown in trays that are vertically stacked on vertical shelving from floor to ceiling. This stacked configuration provides more growing area per floorspace than the non-stacked indoor configuration. Grow lights are mounted above each of the stacked trays, and much closer to the plants than in the greenhouse configuration and non-stacked configuration.